There are several accommodation options in Welwyn Garden City, within walking distance of the Thursday venues.

Hotels:

Travelodge (8 min walk)
Gate House, Fretherne Road, Welwyn Garden City, AL8 6RD. 
Book online or call 0044 (0)8719 846536

Premier Inn (20 min walk)
Stanborough Road,Welwyn Garden City,HertfordshireAL8 6DQ
Book online 

Best Western (30 min walk or 15 min bus)
Homestead Court, Homestead Ln, Welwyn Garden City AL7 4LX
Book online 

Pubs with Rooms:

Pear Tree Inn (20 minute walk)
Hollybush Ln, Welwyn Garden City AL7 4JJ
Book online

Apartments:

Herts Garden House (5 min walk)
36 Parkway, Welwyn Garden City AL8 6HQ
Call 0044 (0)1707 372000

Skyline serviced apartments (8 min walk)
11 Stonehills house, Stonehills, Welwyn Garden City SG1 1AR
Book via Booking.com - requires a minimum two night stay

Homestay:

For private rooms in the area try Airbnb. 

If you are interested in the option of staying with local residents who have volunteered to accommodate visitors please contact Caroline Payne of the Centenary Trust.